CONSOLIDATED STATEMENTS OF EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Cumulative Dividends In Excess Of Earnings	Accumulated Other Comprehensive Loss	Total Stockholders’ Equity	Total Noncontrolling Interests
Balance at Dec. 31, 2015	$ 9,746,317	$ 465,488	$ 11,647,039	$ (2,738,414)	$ (30,470)	$ 9,343,643	$ 402,674
Balance (in shares) at Dec. 31, 2015		465,488
Increase (Decrease) in Stockholders' Equity
Net income	424,587			417,836		417,836	6,751
Other comprehensive income	(268)				(268)	(268)
Issuance of common stock, net	43,072	$ 1,715	41,357			43,072
Issuance of common stock, net (in shares)		1,715
Conversion of DownREIT units to common stock		$ 120	4,902			5,022	(5,022)
Conversion of DownREIT units (in shares)		120
Repurchase of common stock	(3,874)	$ (109)	(3,765)			(3,874)
Repurchase of common stock (in shares)		(109)
Exercise of stock options	2,852	$ 111	2,741			2,852
Exercise of stock options (in shares)		111
Amortization of deferred compensation	9,505		9,505			9,505
Common dividends	(537,061)			(537,061)		(537,061)
Distributions to noncontrolling interests	(12,473)		(36)			(36)	(12,437)
Issuance of noncontrolling interests	3,225						3,225
Deconsolidation of noncontrolling interests	506		(36)	475		439	67
Balance at Jun. 30, 2016	9,676,388	$ 467,325	11,701,707	(2,857,164)	(30,738)	9,281,130	395,258
Balance (in shares) at Jun. 30, 2016		467,325
Balance at Dec. 31, 2016	5,941,308	$ 468,081	8,198,890	(3,089,734)	(29,642)	5,547,595	393,713
Balance (in shares) at Dec. 31, 2016		468,081
Increase (Decrease) in Stockholders' Equity
Net income	486,278			480,528		480,528	5,750
Other comprehensive income	2,353				2,353	2,353
Issuance of common stock, net	13,293	$ 850	12,443			13,293
Issuance of common stock, net (in shares)		850
Conversion of DownREIT units to common stock		$ 68	2,003			2,071	(2,071)
Conversion of DownREIT units (in shares)		68
Repurchase of common stock	(4,361)	$ (141)	(4,220)			(4,361)
Repurchase of common stock (in shares)		(141)
Exercise of stock options	594	$ 21	573			594
Exercise of stock options (in shares)		21
Amortization of deferred compensation	7,092		7,092			7,092
Common dividends	(347,118)			(347,118)		(347,118)
Distributions to noncontrolling interests	(13,087)						(13,087)
Issuance of noncontrolling interests	650						650
Deconsolidation of noncontrolling interests	(58,061)						(58,061)
Balance at Jun. 30, 2017	$ 6,028,941	$ 468,879	$ 8,216,781	$ (2,956,324)	$ (27,289)	$ 5,702,047	$ 326,894
Balance (in shares) at Jun. 30, 2017		468,879